There has been increasing interest in recent years in the use of technology to assess training load in exercise and competitive runners in the field. Efforts have been made to utilize global positioning system (GPS) devices to record running speed and estimate running performance, but these devices exhibit relatively low resolution. A possible candidate that might serve as a means to assess training load for running is the accelerometer. The use of low resolution accelerometers to measure human movement is known. From a physiological perspective, they have commonly been used as mere activity monitors for the coarse-grained measurement of gross movements. In many cases, the goal of using these low resolution accelerometers has been in an attempt to objectively determine energy expenditure during unstructured activities of daily living.
It is known to investigate the relationship between activity monitor accelerometers and VO2 in trained runners in an attempt to objectively quantify external work of a dynamic activity such as running. Further, accelerometers have been used in the field of biomechanics for the purposes of gait analysis. It would be advantageous if there could be developed a method to objectively quantify external work or mechanics of a dynamic activity such as running. Such a method could enhance knowledge of training techniques for exercise activities and racing, and would be applicable to a number of forms of exercise, including running, walking and swimming. Further, it would be advantageous if there could be developed a method analyzing the quality or economy of exercise and other physical activity.